Added HSV example

examples/smoothRainbow.py

@@ -0,0 +1,14 @@
+# Example showing use of HSV colors
+import time
+from neopixel import Neopixel
+
+numpix = 60
+strip = Neopixel(numpix, 0, 0, "GRB")
+
+hue = 0
+while(True):
+    color = strip.colorHSV(hue, 255, 150)
+    strip.fill(color)
+    strip.show()
+    
+    hue += 150